How do I divide the driver value?
Add a single driver to the cube (e.g. Z-rotation)
Go to Graph Editor and switch to Drivers mode
Set Ob/Bone of the variable var to reference the Empty
Enter the Expression var/2 (or var*0.5)




var is equal to the X Location of the Empty, dividing it by 2 halves the "influence" of the location to the rotation of the Cube.